1. Field of the Invention
The present invention relates to a touch recognition apparatus and method in a capacitive touch screen. More particularly, the present invention relates to a touch screen using a parallel resistor and a method for recognizing a touch therein.
2. Description of the Related Art
In general, there are two types of touch screens, namely, a resistive touch screen and a capacitive touch screen. The resistive touch screen has a stacked arrangement, including thin metallic layers that are either electrically conductive or resistive, and detects a change in electric current, caused by a user's contact, to determine the presence of a touch. The capacitive touch screen is coated with materials capable of storing an electric charge and detects a change in capacitance, caused by a user's contact, to determine the presence of a touch.
FIG. 1 is a view illustrating a configuration of a capacitive touch screen according to the related art.
Referring to FIG. 1, a capacitive touch screen 10 includes an X-array and a Y-array. Upon receiving a touch input, the capacitive touch screen senses a variation in capacitance by a combination of the X-array and the Y-array to obtain X- and Y-coordinates. In the capacitive touch screen 10 shown in FIG. 1, a controller 20 sequentially outputs a scan control signal to respective X1, X2, X3, and X4 lines, and senses a variation in capacitance through signals of the Y1, Y2, Y3, and Y4 lines to determine a touched position. That is, the controller 20 scans Y lines connected to an X line in which a scan control signal is activated to sense touched X- and Y-coordinates in such a way that it senses a variation in capacitance in contact points of Y1-Y4 connected to an X1 line when an X1 scan control signal is activated, senses variation in capacitance in contact points of Y1-Y4 connected to an X2 line when an X2 scan control signal is activated, and so forth.
However, in the capacitive touch screen of the related art that uses array schemes with respect to X and Y axes, the number of arrays increases according to the size of the Liquid Crystal Display (LCD). That is, when a touch panel of the touch screen is large, there is a need for a plurality of arrays. Owing to this, the arrays and a structure for controlling the same are complicated. Because there are a large number of lines in the touch screen, the controller needs many scan lines and sensing lines. Furthermore, there is a need for a more complicated Integrated Circuit (IC) that is capable of driving a touch recognition process on the touch panel having the large number of lines and recognizing a touch occurrence.